1. Field of the Invention
The present invention relates generally to conveyor assemblies and, more particularly, to an intermediate discharge for an enclosed roller belt conveyor assembly.
2. Discussion of the Related Art
In various industries, such as those involving agriculture, manufacturing, commercial and industrial applications, it is often necessary to store and transport relatively large amounts of granular materials. In agriculture, for example, it is often necessary to store and transfer substantial quantities of grain from one location to another location. In such instances, grain conveyor assemblies are generally used to move the granular material or grain to and from storage silos or elevators at a first location to grain transportation vehicles at a second location, such as conveyors, grain transport barges, freight trains, trucks, etc.
Grain conveyor assemblies or belt conveyors generally employ a continuous conveyor belt that carries the grain on an upper surface of the conveyor belt. This continuous belt typically rides atop a set of rollers or pulleys. These pulleys include end pulleys which are used for driving the belt and intermediate pulleys which have a V-shape contour to retain and transport the grain, via the belt. The bulk material or grain is generally supplied to the belt conveyor at an inlet and discharged from the belt conveyor at an outlet of the conveyor assembly.
When needed, there are two primary devices used in the bulk material handling industry to remove product or granular material from a belt conveyor at intermediate locations along its length. These devices are known as trippers or plows, which can be designed as stationary or moveable members. Typically these types of applications have been designed and used with open style belt conveyors over the years. The use of open belt conveyors is common throughout many industries. However, some industries are placing more of a restraint on the use of open systems due to safety and environmental concerns. Other methods to accomplish the same purpose as intermediate discharge is by using multiple conveyor systems at each point where a discharge is required. This method, however, is a very expensive alternative and also requires more space to accommodate for the multiple conveyors.
With more safety, environmental and ecological restraints being placed on the belt conveyor industry, the enclosed roller belt conveyor has become more widely accepted and required in handling certain products in many industries. The enclosed roller belt conveyor is designed with an encasement surrounding the belt and mechanical components, thus providing an enclosure for transporting material and confining the airborne particles. These airborne particles caused from transporting and transferring products can have adverse effects. For example, in the grain industry, the containment of dust substantially reduces the risk of explosions. Also, at port facilities, the loading of ships with the enclosed belt eliminates the airborne dust particles that can negatively effect the environment. Additionally, the belt support rollers are within the enclosure and remove the risk of injury from these rotating components and moving belt. Therefore, this style of conveyor addresses the safety, environmental and ecological concerns related to many industries.
The dilemma facing the designers of enclosed roller belt conveyor systems is to incorporate features of the open style belt conveyor without the boundary of the enclosure, while maintaining the concerns discussed above. For example, one type of enclosed intermediate discharged system employs a belt conveyor assembly which ramps up or elevates the belt progressively over an extended length up to a discharge area where the belt is routed about a lower set of pulleys creating a stepped shape along the belt conveyor. At this stepped region, a tiltable bucket or direction member captures the bulk material dropping from the elevated portion of the belt conveyor to the lower portion of the belt conveyor to provide an intermediate discharge in this stepped area. If this discharge member or bucket is again actuated, the bulk material is simply dropped along the belt conveyor to a final outlet destination without having an intermediate discharge.
However, this type of system has many disadvantages. For example, by ramping up the conveyor assembly, this requires additional power output to drive the overall conveyor assembly and also requires a longer intermediate discharge region up to and generally over forty (40) feet long, which is elevated from a beginning point to an ending point of over generally four (4) feet. This prevents having several intermediate discharges positioned relatively close to one another, thereby, in some instances, requiring multiple conveyor assemblies to achieve multiple intermediate discharges. Additionally, these types of systems generally may not be retrofitted with existing conveyor belt assemblies due to the size and overall construction involved, thereby adding additional costs should it be desired to have an intermediate discharge along a conveyor assembly. Finally, these types of conveyor assemblies may only be driven in a single direction because of the step formed in the conveyor, thereby inhibiting a bi-directional operation of the conveyor assembly.
What is needed then is an improved intermediate discharge for an enclosed roller belt conveyor assembly, which does not suffer from the above-mentioned disadvantages. This will, in turn, enable bi-directional movement of the belt conveyor; reduce the power consumption generally required for intermediate discharge operations; provide a more compact and versatile intermediate discharge assembly, which can be retrofitted to existing conveyor belt assemblies; and provide an intermediate discharge assembly that is shorter in length and narrower in width to enable multiple intermediate discharges within a smaller space without having to configure the conveyor belt in a stepped configuration. It is, therefore, an object of the present invention to provide such an intermediate discharge for an enclosed roller belt conveyor assembly.
In accordance with the teachings of one preferred embodiment of the present invention, an intermediate discharge assembly to remove granular material from a conveyor belt used in an enclosed roller belt conveyor assembly includes a first pair of leading and trailing pulleys, a second pair of leading and trailing pulleys and a plow. The first pair of leading and trailing pulleys is operable to support the conveyor belt in a substantially concave manner. The second pair of leading and trailing pulleys is operable to support the conveyor belt in a substantially flat manner. The plow is positioned between the first and second pairs of leading and trailing pulleys and is operable to remove the granular material from the conveyor belt. When the first pair of leading and trailing pulleys supports the conveyor belt, the plow is elevated above the conveyor belt, such that the granular material passes through the intermediate discharge assembly. When the second pair of leading and trailing pulleys supports the conveyor belt, the plow is positioned atop the substantially flat conveyor belt, such that the granular material is removed from the conveyor belt.
In another preferred embodiment, the intermediate discharge assembly to remove granular material from a conveyor belt used in an enclosed roller belt conveyor assembly includes a plow support frame platform and a plow. The plow support frame platform is positioned below the conveyor belt and is operable to be located in a first position and a second position. The plow is positioned above the conveyor belt and is operable to be located in a first position and a second position. When the plow support frame platform and the plow are each located in the first position, the conveyor belt passes over the plow support frame platform and the granular material passes through the intermediate discharge assembly. When the plow support frame platform and the plow are located in the second position, the plow support frame platform is elevated from the first position to substantially support the conveyor belt and the plow is lowered atop the conveyor belt to substantially remove the granular material from the conveyor belt.
In yet another preferred embodiment, a method to remove granular material at an intermediate location along a conveyor belt used in an enclosed roller belt assembly is provided. This method includes locating the conveyor belt at a first position to enable the granular material to pass by an intermediate location. This method further includes elevating the conveyor belt to a second position at the intermediate location to permit removal of the granular material at the intermediate location.
Use of the present invention provides an intermediate discharge assembly to remove granular material from a conveyor belt used in an enclosed roller belt conveyor assembly. As a result, the aforementioned disadvantages associated with existing conveyor assemblies have been substantially reduced or eliminated.
Further areas of applicability of the present invention will become apparent from the detailed description provided hereinafter. It should be understood that the detailed description and specific examples, while indicating the preferred embodiment of the invention, are intended for purposes of illustration only and are not intended to limit the scope of the invention.